Plunger packing



March 6, 1934. A. A. LANE PLUNGER PACKING Filed Dec. 16, 1930 a y m AA. la

M dams Patented Mar. 6, 1934 UNITED STATES PATENT OFFICE PLUNGER PACKING poration of Delaware Application December 16, 1930, Serial No. 502,773

8 Claims.

This invention relates to plunger packings, particularly packings of the metallic ring type which are designed to be assembled on a piston that reciprocates in a cylindrical bore.

The present invention constitutes a modification of, and in certain respects an improvement upon, the invention disclosed in a pending application Serial No. 500,360, filed December 5, 1930. In said application there is shown a very effective packing of the metallic ring type applied to the plunger of a deep well pump. The packing consists of a series of alternately contracting and expanding spring rings with their side surfaces in free sliding engagement. The contracting as well as the expanding rings are slidable axially of the plunger and hence adapted to take up any play resulting from side wear. The expanding rings spring outwardly and engage the bore of a cylinder within which the plunger reciprocates, and are capable, when removed from the cylinder, of springing outwardly to a greater diameter than that of the cylinder bore. Hence, some difiiculty is encountered when attempting to insert the packed plunger in its cylinder, in squeezing the expanding rings into proper relationship with the plunger and the end of the bore. This difficulty is not so great where the cylinder and packing are accessible and within view and the proper tools can be used, but when the cylinder is not readily accessible (as, for example, in some forms of deep well pumps) the difficulty is practically insurmountable. At least, it results in great inconvenience and often in damage.

There are two general types of pumps used in deep wells, known in the industry as liner type and common barrel pumps respectively. In the liner type, as distinguished from the common barrel pump, the plunger does not operate directly within the main barrel or casing that is fastened at the lower end of the flow line, but reciprocates in a separate liner that has been assembled on the plunger at the earths surface and then lowered down into the well and snapped into place in the outer or main casing. In the common barrel pump, on the other hand, the plunger is lowered into the well without any liner, and the working barrel, which is permanently secured at the bottom of the flow line, itself provides the pump cylinder within which the plunger reciprocates during operation.

The alternate contracting and expanding rings of the pending application, previously mentioned, are shown applied to a pump of the liner type, with the liner or working cylinder preferably assembled around the plunger at the earths surface. Hence the expansibility of certain of the rings caused no interference or trouble during the operation of placing the plunger within its working cylinder. No one, however, has successfully attempted to utilize the desirable expansion spring rings on the plunger of a pump of the common barrel type. The primary reason for lack of success in such endeavors is that the expanding rings on the plunger, in being lowered into the well, must pass through a long upper enlarged 55 section of the common barrel, and must then, while freely suspended without any means for properly aligning them, be contracted and forced into a lower section forming the working cylinder of the common barrel. The last step is extremely difiicult, if not impossible, and the rings may be sprung into distortion, chipped or otherwise injured.

Accordingly, it is one of the major objects of the present invention to provide a packing, embody- 7 ing expanding spring rings, which may be utilized, effectively and without damage or inconvenience, upon the plunger of any type of well pump, including the common barrel type.

It is a further object, in a well pump, to utilize 8o self-expanding rings on the working plunger and to provide means at the entrance of the working barrel for centering and guiding the rings into the barrel during the initial insertion of the plunger. In this connection it is another object of the present invention to limit the outward expansion of the rings and to so design the firstentering ring of the set that it is permitted to expand further than the others and thus protect the latter during the operation of inserting the plunger. The first-entering ring preferably is formed of a material that is substantially indestructible and that may be different from that of the other rings.

My invention is of broader application than that specifically outlined above in connection with deep well pumps, and hence some of its objects may be stated more comprehensively, as follows:

It is the general object of this invention to devise a new and improved piston packing, involving self-expanding rings which may be assembled upon the piston and then inserted with the latter into a cylinder without difiiculty.

A further object of the present invention resides in the provision of a piston packing com- 5 prising a series of alternating expansible and inexpansible rings, with cooperating means on the rings to limit the outward movement of the expansible rings; and to so design such limiting means that its incorporation will not detract from the desirable characteristics, (appearing later), of the alternating ring assembly.

These and other objects will fully appear from a study of the following detailed description and appended claims, especially when taken in connection with the accompanying drawing, where- Figure 1 shows, in vertical longitudinal section,

a portion of a well pump of the common barrel 10 type with a preferred embodiment of my invention incorporated therein.

Figure 2 represents a central cross section taken on one of the contracting rings of Figure 1, greatly enlarged.

Figure 3 discloses, in a view similar to Figure 2, one of the self-expanding rings of Figure 1, in a semi-compressed position.

Figure 4 is a magnified view of a portion of the structure shown in Figure 1, such portion being substantially included within the circle 04 drawn on Figure 1.

Figure 5 is an enlarged detail view similar to Figure 4, but showing the plunger and rings after they have been pushed downwardly in Figure 1 into the working barrel in which the plunger is designed to reciprocate during operation.

With continued reference to the drawing, wherein like characters are employed to designate like parts, the letters B and C indicate two sections of a deep well pump of the common barrel type. The section B forms the workingbarrel of the pump proper and is connected at its upper end by a sleeve coupling 6 with the lower end of the section C, the latter forming a casing or flow line through which the pumped fluid is discharged toward the earths surface.

A plunger or piston P has an integral stem 7 provided with a threaded end 8 for connecting it with a sucker rod string (not shown). This plunger is designed to be lowered into the barrel B by way of the casing C, as illustrated, and thereafter to reciprocate in said barrel. Reciprocation of the plunger causes fluid to be pumped in a substantially conventional manner. The plunger has a bore 8 in the lower end of which is mounted a traveling valve assembly comprising a cage 9, a seating ring 10 upon which rests a ball 12, and a special retaining member 13, cored as at 14, adapted to be screwed into the end of the bore to lock the seat and cage in position. This valve assembly cooperates with a standing valve assembly (not shown) for forcing fluid upwardly through the bore 8 and thence into the casing C by way of a set of ports 15 in the stem 7.

The body of the plunger P is reduced to form a cylindrical surface 16 terminating in a shoulder in the nature of an annular ledge 1'7. A series of alternately contracting and expanding rings 18 and 19 respectively, are arranged in superposed relation upon the ledge to form a packing for the plunger. Each ring 18 is a metallic one split at one place as at 20 (see'Fig. 2) to form a self-contracting spring ring. One of its sides is flat, as at 22, and its other side is cut to produce a cylindrical flange 23 surrounding a resulting shouldered surface 24 on the ring. Each ring split at one piece, as at 25 (see Fig. 3) to renhereafter be designated by numeral 19' for reasons later to appear, comprises a metallic spring ring split at one place, as at 25 (see Fig. 3), to render it self-expanding. On one side it is flat, as at 26, and on the other it is peripherally grooved to form a lip or cylindrical flange 27 surrounded by a. resulting shouldered surface 28.

The ring 19 of Figure 3 is shown in a semiment.

compressed, rather than its natural position. In the packing assembly it. is held in such semi compressed position as a result of the reception of its flange 2'7 within the flange 23 of the selfcontracting ring 18 of Figure 2. The cooperating flanges 23 and 27 are of the same width so that the former may sealingly engage the surface 28 of the ring 19, and the latter may sealingly engage the surface 24 of the ring 18. In the assembly, then, the flanged side of each contracting ring cooperates with the flanged side of an adjacent expanding ring to resist and limit the outward expansion of the latter, and the flat side 22 of the contracting ring sealingly engages the fiat side 26 of another expansion ring. A simple snap ring 29 is employed (see Fig. 1) for holding the several.alternating rings in assembled relation upon the plunger.

The chief advantages of the above described interlocking flange arrangement are that the contracting rings serve to center the expanding rings relative to the plunger axis and that they prevent the expanding rings from enlarging to their full outer limit of expansion. As a result, the plunger can readily be inserted in its operating cylinder without certain portions (the expansion rings) of the packing catching upon or otherwise interfering with the end of the cylinder to become damaged or to tend to prevent the plunger insertion. This is of great importance in well pumps where the plunger has to be lowered down into the well and there entered into an invisible working barrel. Moreover, during the lowering operation the plunger passes through a flow casing (C) and if its expanding rings were not centered and compressed they would strike the walls and joints of the casing.

In Figure 1 the plunger is shown lowered to a point where its packing is about to enter the barrel B. The internal diameter of the latter necessarily is and must be less than the external diameter of the expanding rings, in their semi-compressed and interlocked position, in order that they may be further compressed by the barrel bore to seal the latter during plunger reciprocation. The upper edge of the barrel B is uniformly curved, as at 30 or beveled, to provide a smooth surface for compressing the expansion rings and guiding them into the bore of the barrel.

In Figure 4 the plunger is shown inserted in the barrel, with the packing in its position normally occupied during pump operation. The contracting rings are fitting snugly upon the plunger, and the expansion rings are compressed inwardly by the barrel bore beyond their position of Figure 4, as a result of which their flanges are no longer inv engagement with the cooperating flanges of the contracting rings. Hence the latter do not prevent the peripheral surfaces of the expanding rings from bearing against the barrel bore in sealing relationship therewith.

It will be observed that the lowermost expanding ring, designated as 19', is of slightly different design than the others. Its thickness is a little greater so that, as seen in Figure 4, its peripheral surface extends outwardly beyond those of the others by a distance d, when the alternating rings are in their position of interlocked engage- This is done so that, when lowering the plunger through the casing C, the ring 19' will be subjected to all of any bumps or destructive shocks resulting from interference with the casing walls, joints, etc. The ring 19' may be made of steel so that it will not be damaged by the ou est) shocks, and it thus protects the other expansion rings, 19, by guiding them through a clear un= obstructed space. As a result the rings 19, which preferably are formed of cast iron, will not become chipped, distorted or otherwise damaged.

A similar enlarged ring 19' may be employed at the top of the packing, if desired, for aiding in the protection of the intermediate rings when the plunger is withdrawn for repairs or other purposes.

It will be understood that the inventive features above described are adaptable for application in other forms and combinations, and for other uses than in a particular type of deep well pump. In connection with the latter, however, there are certain advantages in the use of alternately contracting and expanding rings, which advantages are not lostby' the addition of the interlocking flanges of this invention. Some of these advantages are related below.

In practically all oil wells, some sand is present and finds its way into the pumps to abrade the parts of the latter and damage the packing. Where expanding metallic rings are used, however, the sand particles can not get past the sharp edges of the rings nor embed themselves in any manner. A standard plunger may be provided for use under any one of a number of conditions, such as well depth, pressure, etc. This is because the plunger is of uniform diameter to permit all of the rings to slide axially, and hence any number of rings may be used by substituting spacers of predetermined lengths to take the place of any subtracted rings.

Another advantage, not restricted to well pumps, is that since all of the rings are slidable axially of the plunger, they may be adjusted axially to take up for any wear on the side surfaces of the rings. Leakage thus is easily prevented or remedied. The same is true in the special ring assembly of this invention, since any wear on the side surfaces of the ring flanges can be compensated for.

The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiment is therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

What is claimed is:

1. In combination with a plunger designed for reciprocation, a packing mounted on the plunger in surrounding relation thereto, said packing comprising a set of expanding rings, and means fitted closely upon the plunger in surface contact therewith for limiting the outward movement of each of said expanding rings and for sealing the surface of the plunger against longitudinal leakage.

2. 'In the combination defined in claim 1, said limiting means comprising a set of nonexpanding rings surrounding said plunger in alternating relationship with said expanding rings and at least equal in strength to the latter.

3. In the combination defined in claim 1, said plunger being of uniform size through the packing, and said limiting means comprising a number of contracting rings alternated with said expanding rings and provided with means designed to engage said expanding rings when the latter have expanded to predetermined outer limits.

For use in combination with a cylindrical member, a packing ring assembly comprising a series of alternated contracting and expanding rings axially aligned to form a packing sleeve for sealing the surface of said member against longitudinal leakage, and complemental means on said rings interengaged so that the contracting rings limit the outward expansion of said expanding rings.

5. In combination, in a deep well pump, ,a working barrel, a casing superposed on said barrel in aligned series relationship therewith, the inner diameter of said barrel being less than the inner diameter of said casing, a plunger designed to be passed through said casing and thence into said barrel, and a packing on said plunger, said packing comprising a set of rings designed to expand outwardly to a diameter greater than said inner diameter of the barrel, and means coacting with said rings to prevent their expansion to an outer diameter as great as the inner diameter of said casing.

6. In combination, in a deep well pump, a working barrel, a casing having an internal diameter larger than that of said barrel and being superposed upon said barrel in alignment therewith, a plunger designed to be passed through said casing into said barrel for reciprocation within the latter, and a packing fitted upon said plunger, said packing comprising a plurality of self-expanding rings and complemental means in coacting interengagement with said rings to restrain the latter from maximum self-expansion while the plunger is being passed through'said casing, but to permit unresisted expansion of said rings against the barrel bore after their insertion within said barrel.

7. In combination, in a deep well pump, a Working barrel; a casing of larger diameter than said barrel and superposed thereon and in alignment therewith; a plunger in said barrel and designed to be passed through said casing for reciprocation within the barrel; and a packing fitted upon said plunger; said packing comprising a plurality of self-expanding rings and complemental means in co-acting interengagement with said rings to restrain the latter from maximum self-expansion prior to their insertion within said barrel, the last expanding ring at one end of the packing being fabricated of less brittle material than the others and having its periphery, when unrestrained by the barrel, projecting outwardly beyond the peripheries of the other rings whereby the edges of said other rings are protected when the plunger is being passed through the casing.

8. In combination in a deep well pump, a working barrel; a casing superposed upon said barrel in alignment therewith; a plunger designed to be passed through said casing into said barrel for reciprocation within the latter;

and a packing fitted upon said plunger said packing comprising a plurality of self-expanding rings and complemental means in coacting interengagement with said rings to restrain the latter from maximum self-expansion prior to their insertion within said barrel; said plunger being of uniform diameter within the packing, and said complemental restraining means comprising a plurality of self-contracting rings in alternating arrangement with said expanding rings and in surface engagement with said uniform plunger.

ABBOT A. LANE. 

